3520B Issue From A Friend of Mine

[Matt Hutchinson]

So, a friend of mine has a 3520B, and he does a lot of 32" diameter platters outboard. He uses kiln dried wood that's very balanced, and he starts thing off around 400 rpms. After it's trued up, he kicks it up to 600-800 rpms (too high if you ask me).

But here's the issue: The VFD cuts out, with an overload message on the display. He isn't putting the system under any significant duress, but the machine just doesn't want to stay on.

Anyone have a similar issue or have a solution? Thanks!!

Hutch

[Reed Gray]

First guess would be that he is in the high speed range. Weight wouldn't be the problem, but the large diameter torque issue would be a possible over load situation. When I first got my A, it would always trip when I turned it off with a 14 inch bowl blank on. Turned the brake time down, and switched to low speed range (they would help you adjust parameters on the phase converter back then), and no problem.

robo hippy

[Dick Strauss]

Reed is right on track...

You need the extra torque that the low speed pulley gives to get a piece that size running. You don't want to slow it down too quickly otherwise it might overheat the braking resistors or DC voltage injection system of the VFD.

[Jon Nuckles]

Ditto, here. I have no problem getting huge and heavy blanks started in the high speed range, but my 3520B occasionally trips when braking them. If I switch to low gear, the problem disappears. (And no, I'm not spinning big and unbalanced blanks at 2000 rpm; I am just too lazy to change the belt if I don't have to.)

[Matt Hutchinson]

Thanks all, I will let him know!

Hutch